This table describes how to address common errors you can encounter while working with the
Database Toolbox™ Interface for Apache Cassandra® Database.

Error Message

Probable Cause

Resolution

Cassandra exception: error
message

The Cassandra®
Java® driver throws an error. Sometimes the error can result from an invalid
Cassandra Query Language (CQL) query.

Use the error message to troubleshoot the issue. If you are using a CQL
query, ensure that you enter a valid CQL query in the query input
argument of the executecql function.

Invalid Cassandra connection.

The Cassandra database connection is closed.

Create a new Cassandra database connection using the cassandra function.

Unable to find keyspacename keyspace. View
the Keyspaces property to list the keyspaces in the cluster.

The specified keyspace does not exist in the Cassandra database.

Specify a keyspace that exists in the Cassandra database. To view the keyspaces, access the
Keyspaces property of the cassandra object.

Unable to find tablename table. View the
tablenames function to list the tables in the keyspace.

The specified Cassandra database table does not exist in the Cassandra database.

Specify a Cassandra database table that exists in the Cassandra database. To view the Cassandra database tables, use the tablenames function.

Too many inputs. Table tablename has
n primary keys, but n+1 were
specified.

You specify more key values than primary keys in the
partitionRead function. Or, you do not specify key values for
all primary keys.

Specify the correct number of key values for the primary keys. To view the
key values, use the keyValues output argument of the columninfo function.

Primary keys of type datatype must be a
string vector, character vector, or a 1-dimensional cell array of character
vectors.

You specify a value that does not contain text data for a key that has a
text data type.

Use a string scalar, character vector, or one-dimensional cell array of
character vectors to specify text data.

Primary keys of type datatype must be a
numeric vector.

You specify a value that does not contain numeric data for a key that has a
numeric data type.

Use a numeric vector to specify numeric data.

Primary keys of type datatype must be
either a numeric vector or a 1-dimensional cell array of numeric
vectors.

You specify a value that does not contain numeric data for a key that has a
blob data type.

Use a numeric vector or one-dimensional cell array of numeric vectors to
specify data that has the blob data type.

Primary keys of type datatype must be a
logical or numeric vector.

You specify a value that does not contain numeric or logical data for a key
that has a boolean data type.

Use a numeric or logical vector to specify data that has the
boolean data type.

Primary keys of type datatype must be a
datetime vector, string vector, character vector, or cell array of character
vectors.

You specify a value that does not contain numeric or text data for a key
that has a date or timestamp data
type.

Use a datetime array, string scalar, character vector,
or cell array of character vectors to specify data that has the
date or timestamp data type.

Primary keys of type datatype must be a
duration vector, string vector, character vector, or cell array of character
vectors.

You specify a value that does not contain numeric or text data for a key
that has a time data type.

Use a duration array, string scalar, character vector,
or cell array of character vectors to specify data that has the
time data type.

Primary keys of type datatype are not
supported by the partitionRead function. To import data from
tablename table, either use the partitionRead function
with no primary key values, or use the executecql function to execute a CQL
query.

You specify a data type of a primary key that is not supported in the
partitionRead function (for example, user-defined type (UDT)
or tuple).

Execute a CQL query using the executecql function to filter for the primary keys that the partitionRead function does not support.

UPSERT requires values for the following primary key columns to be
specified: columns.

You omit one or more primary keys in the Cassandra database table.

Specify a variable in the MATLAB® table for each primary key in the Cassandra database table when you insert or update data using the upsert
function.

One or more variables in DATA are not a column in the Cassandra table.
Use COLUMNINFO to list all columns defined for the table.

One or more variable names in the MATLAB table do not match any column names in the Cassandra database table.

Verify the names of the columns in the Cassandra database table by using the columninfo function. Then, adjust the names of the variables in the
MATLAB table accordingly.